What happens to old bitcoin addresses? I've read that they never get destroyed, but do they get reassigned?
Bitcoin addresses are not reused or reassigned to anybody under any circumstances.
The story is I sent some bitcoin to an exchange using an address I've used with them before, but then found out that they had just retired/stopped using that address.
Having investigated this following @MCCCS answer, the following is information about the addresses provided by Blockhair support:
In fact, there are no addresses on the Bitcoin blockchain. There are
only scripts, some of them are standard and can be converted to a
Bitcoin address, some of them can’t — like nulldata (OP_RETURN)
outputs, nonstandard, and bare ...
Bitcoin addresses are essentially just large random numbers. So there's nothing to destroy or reassign - it's just a number.
When you "create" a new address, what you're really doing is just picking two random numbers (that are cryptographically linked to each other) called a "private key" and a "public key". The public key is ...
You can use a self-hosted (but low-burden!) instance of Esplora.
Blockstream is also exposing an instance for free (at the moment) at blockstream.info.
Disclaimer: if you take part of Bitcoin as an economic actor (as an application providing account balances may imply), you should really consider using your own source of truth and self-host the instance. It'...
No. There are multiple kinds of addresses in common use:
A Pay to Public Key Hash (P2PKH) address, beginning with a 1... uses a Hash160 (Sha256 followed by RipeMD160) of the public key. The public key is not revealed until this output is spent, as the spending transaction will include the public key in its scriptSig.
A Pay to Script Hash (P2SH) address, ...
Can I recover btc sent to an incorrect address?
Confirmed Bitcoin transactions cannot be cancelled, reversed, undone or recovered.
The only person who can give you your money back is the recipient, by creating a new transaction to send the same amount back to you.
I realize now that I had a malware copy of electrum
If the initial mishap was due to a ...
Modern wallets are hierarchical deterministic (HD) wallets.
A root key is used to derive an effectively infinite number of private keys using systems such as BIP32.
Each derivation results in a single public/private keypair, and hence a single address at that level.
Prior to the usage of HD wallets, things were a bit more straighforward - every time you ...
No, and in fact, deleting a file is not destructive enough.
File deletion typically does not actually delete the file. Filesystems will just mark a file as deleted and allow it to be overwritten. If the file does not end up overwritten, it can be recovered from the drive using some forensic tools.
Furthermore, the way that the hard drive itself writes data ...
Technically speaking, is it possible to reuse a change address from a previous transaction and make it a receive address?
Technically that would be possible. The network rules have no concept of change or receive addresses - it's just a scriptPubKey that coins are sent to.
What are the pros and cons of doing so?
I see no reason why you'd want to do that. ...
Looking at the address you provided in a block explorer(OXT Explorer)
it seems your exchange has been reusing that address quite a bit since December to now and has not really cut down on using it. I do not think they have retired the address and it is definitely still under their control.
Is there an official network ...
how did Electrum create a new address?
Electrum, and most modern wallets are Hierarchical Deterministic (HD) Wallets. They derive a series of private-keys from the "master private-key".
If you always start with the same seed phrase you get the same master private-key. Electrum uses its own unique method for seed phrases. Most wallets with seed-...
How Bitcoin nodes validate a new wallet
Bitcoin nodes validate blocks and they validate the transactions within those blocks
Other nodes don't have access to your wallet and can't validate it or anything in it.
I mean, what if this wallet already exist?
No one knows or cares if the private-key initially generated by your wallet already exists. ...
Which kind of address do you want?
Assuming that you have compressed public key(compressed_public_key.txt), to generate P2PKH you can use these commands (hash160 and encoding with base58)
ADDR_RIPEMD160=$(printf $(cat compressed_public_key.txt | xxd -r -p | openssl sha256| sed 's/^.* //') |xxd -r -p | openssl ripemd160 | sed 's/^.* //')
Well, it's very simple. Traditional wallets just generate multiple private keys.
A private key is basically a randomly generated number. You can generate several of those, and store them all in a file.
This poses a challenge with backups, because you have to keep saving new backups - and even if you do, as you continue using the wallet, your coins could be ...
First of all, since a single key can be represented by tons of different address types, let's assume what you meant to ask is about private keys. As @dave_thompson_085 points out, most addresses are actually limited to a 2^160 space by a RIPEMD hash. So that number may be closer to the actual amount of keys you'd need to sweep "all" the bitcoin.
Can it safely be said that the first input in the inputs of the transaction is the sender's?
No, no such ordering exists.
Transactions consume UTXOs as inputs, and create new UTXOs as outputs. A transaction can have multiple inputs from one person, or inputs from multiple people. In some cases, more than one person can own an input. So there isn't really ...
Answering this question requires first defining what an address means.
Historically (before BIP16 activated in 2012) an address was a synonym with a "public key identifier", as there were no addresses for multisig constructions or anything like that. Under this interpretation, pay-to-pubkey or pay-to-pubkey-hash outputs would be seen as having the ...
There are approximately 800,000 unique addresses on the blockchain with some Bitcoin held at those addresses at the present time according to blockchain.com.
Let's assume these addresses are all bech32 (to simplify the calculation, in reality these are the minority).
The witness program in a bech32 SegWit v0 P2WSH address is 32 bytes. In theory this means ...
No, it's not known, and information like that generally won't be publicly released. Bitcoin addresses aren't generally publicly associated with the real-life identities of their owners.
I would expect a company like Tesla to have the bulk of their cryptocurrency assets stored in institutional custody regardless, for liability and regulatory reasons.
Individual address private keys begin with 5,L or K. What you're calling root private keys are actually called extended private keys and they begin with ?prv where ? is either x,z,y,Y,Z. You can see examples of those here. So that's how you tell the difference.
The wiki says that
A Bitcoin address is an identifier of 26-35 alphanumeric characters.
This information is now outdated but it was true at the time this question was asked look at morsecoder's answer. With the introduction of Bech32 type addresses in 2017, the minimum and maximum length of a Bitcoin address have changed.
According to BIP 173:
signmessage and verifymessage only work with legacy type addresses. They do not work with segwit addresses. There is ongoing work to introduce a new message signing standard that will work regardless of address type.
Some discussion about why they only work on legacy addresses can be found in this issue: https://github.com/bitcoin/bitcoin/issues/10542
Both "1LoVG.." and the other one are valid legacy (1...) addresses made using the same private key. They are different since one of them uses the compressed public key (you might want to look this up) while 1GAehh7 uses the uncompressed public key. Always use the same compress-format for an address, and it's advisable to create new addresses in ...
The Bitcoin URI scheme is defined in BIP21:
Bitcoin URIs follow the general format for URIs as set forth in RFC
3986. The path component consists of a bitcoin address, and the query component provides additional payment options.
You can read through the entire RFC document or the summary on Wikipedia which answers your question:
An optional authority ...
You can never understand someone's trustworthiness by looking at their balance history.
It's common to use a new address to receive a new transaction every time. This may be to make it harder for a customer to see another customer's balance or more importantly, understand who sent them money (for example, 2 people buy the same thing costing $500, while you ...
A single output is roughly 34 bytes per output regardless of whether the output represents a standard address or multisig address. Is this correct?
Yes, in modern Bitcoin transactions the size of producing an output (ie, paying to an address) is constant and has no relation to the size of the actual script. For native segwit outputs the size is somewhat ...
There is no relation at all between the two addresses, except that they're owned by the same person/wallet.
At the protocol level, "change" does not exist. It's just another output (with a corresponding address), indistinguishable from normal "payment" outputs. It is your wallet that's creating it: it needs a place to send the remainder ...